We propose an epidemiological case-control study of gallbladder cancer in Los Angeles County Hispanics for the purpose of evaluating the role of reproductive history, estrogenic activity, Hispanic diet, Amerindian inheritance, past GI and metabolic disease, and environmental exposures in the etiology of that disease. We will attempt to distinguish between the causes of gallbladder cancer and the causes fo cholelithiasis. The cases will consist of all female cases of gallbladder cancer occurring in Los Angeles County in three years; controls will consist of matched persons chosen from the neighborhood of the case and matched cases undergoing cholecystectomy at the hospital in which the cancer case was diagnosed. A personal interview will elicit information about reproductive history, medical history and drug use, Hispanic diet, and environmental exposures; blood will be taken to assess evidence of bile lithogenicity, the presence of Gm allotypes indicating Amerindian inheritance, serologic evidence of past typhoid infection, and evidences of estrogenic activity. State-of-the-art techniques, including logistic regression, will be employed in the analysis.